1. Field of the Invention
The present invention relates generally to a two-piece clamp for securing elongated cylindrical members, more particularly to, a two-piece clamp with a cushion for securing an elongated cylindrical member therein.
2. Description of Related Art
Presently, there exists a clamp assembly having two clamp halves and a stud non-rotatably anchored on one of the clamp halves. The stud includes an integral or separable spacer portion which controls the clamping force exerted on the tubing and prevents deformation of the tubing when the stud assembly is tightened.
An example of such a clamp assembly is disclosed in U.S. Pat. No. 4,516,296, issued May 14, 1985, by inventor Clarence A. Sherman, which is hereby incorporated by reference. The patented clamp assembly includes a cushion insert for indirectly engaging the tubing through the elastomeric cushion insert which partially encircles the tubing and is retained within the clamp assembly as illustrated in FIG. 1. The cushion insert 10 includes a generally planar base portion 12 with upwardly and inwardly extending arcuate side walls 14 that substantially encompass the tubing. The ends of the side flanges 14 form a gap 16. The side walls 14 form a smooth continuous passageway 18 extending axially through the cushion insert 10 in which the tubing is disposed. The side walls 14 also include end flanges 20 extending outwardly at the ends of the cushion insert 10 to limit the relative axial movement between a clamp half disposed between the end flanges 20 and the cushion insert 10.
One disadvantage of the above patented clamp assembly is that when small diameter tubes are used, e.g. one-half inch diameter, a large amount of force must be exerted by the operator on the cushion insert to spread the side walls of the cushion insert apart to fit over and about the tube. As a result, the cushion inserts were slid or disposed about one end of the tubing and moved to the desired position along the tubing. Another disadvantage of the above patented clamp assembly is that the cushion insert is used for generally continuous tubing of constant diameter which is used for fluid lines running from a power supply to a machine or the like, e.g. in the fluid power market. Also, the patented clamp assembly is used for typically thin walled copper tubing to prevent the tubing from being deformed if the clamp assembly is over-tightened. However, if the patented clamp assembly is used for thick walled steel tubing or the like, the spacer prevents the clamp halves from being tightened together to the extent required to prevent leaking of a junction between tubing or relative movement between the tubing and clamp assembly.
Currently, a rail mounted system or clamp assembly is used in the fluid power market as illustrated in FIG. 2. Typically, the rail mounted clamp assembly 21 includes a junction adapter or fitting 22 having a square or hexagon nut 23 formed on its outer surface with male or female threaded ends 24. The assembly also includes a rectangular tube or housing 25 about the nut 23 which is adapted to be secured to a support surface. A pair of cylindrical members 26 pass through the housing 25 on both sides of the adapter 22 to prevent rotation of the adapter 22. The cylindrical member 26 has a nut or base 27 at one end abutting the outside of the housing 25 and a fastener 28 which threadably engages the other end of the cylindrical member 26 to secure it to the housing 25. Typical examples of such rail mounted clamp assemblies used in the fluid power market are disclosed in U.S. Pat. No. 3,397,431, issued Aug. 20, 1978, by inventor W. R. Walker and No. 3,414,220, issued Dec. 3, 1968, by inventor W. R. Walker.
One disadvantage of the above rail mounted clamp assembly is that it must be disassembled to attach the tubing to the junction adapter or other assembly. Another disadvantage is that a pair of cylindrical members must be used on each side of the nut or the adapter to prevent it from rotating in the housing.
Some examples of other clamp assemblies are disclosed in U.S. Pat. No. 4,037,810, issued July 26, 1977, by inventor Harold T. Pate and U.S. Pat. No. 4,442,994, issued Apr. 17, 1984, by inventor Duane D. Logsdon. Although both of these patents disclose a clamp with a point of flexure, Pate merely discloses a plastic cap or lid hinged to the remaining portion of the plastic clamp to secure tubing therein. Also, Logsdon's pipe hanger would be unsuitable to support the weight of the fluid in the tubing when used for fluid lines in the fluid power market. Further, Logsdon's pipe hanger would be unsuitable for non-constant diameter and non-smooth outer surfaced or discontinuous pipe or tubing and channel or rail mounted systems.
It is, therefore, one object of the present invention to provide an easy-to-use cushion insert to fit over tubing or other cylindrical members of relatively small diameters.
It is another object of the present invention to provide a clamp assembly which can be used for fluid lines in the fluid power market.
It is a further object of the present invention to provide a cushion insert that can be used for non-constant diameter and non-smooth outer surface or discontinuous tubing or other cylindrical members.
It is a still further object of the present invention to provide a clamp assembly that can support the weight of the fluid and tubing or other cylindrical member.
It is another object of the present invention to provide a clamp assembly which prevents rotation of the tubing or other cylindrical member within the clamp assembly.
It is a further object of the present invention to provide a clamp assembly which does not require disassembly to attach the tubing or other cylindrical member to it.